Friday, 6 August 2010

I like lakes, you like lakes, Luke Luck likes lakes, you get the picture but when lakes leak with little or lack of warning, there’s a lot less to like. This look at 10 drained lakes of the past and present shows the gravity of the situation when Mother Nature – or, on occasion, the errant hand of Man – suddenly decides to pull the plug.

Tempe Town Lake, Arizona, USA

Tempe Town Lake is a 2-mile long artificial lake that runs through the center of Tempe, Arizona, USA. The lake sits within the bed of the Salt River, which is almost always dry due to diversion of the river’s water for agricultural use at various points upstream.

The lake is only about 13 feet deep on average and is held in place by innovative inflatable dams at either end. The Dams allow the Salt River to flow along its natural course at times when storms and flooding create an unusually high level of water in the river bed.

On July 20, 2010, the west side of Tempe Town Lake’s outflow dam suffered (for want of a better term) a blowout that allowed most of the lake’s water to quickly drain into the Salt River. Most of the approximately 10,000 fish living in the lake were swept downstream and an alligator named Tuesday was released into the remaining pools of water to eat what fish remained.

Lake Delhi, Iowa, USA

The Delhi Dam, on the Maquoketa River south of Delhi, Iowa, was built over a 7-year period from 1922 to 1929. Lake Delhi was created behind the dam and over the succeeding decades proved to be a much-desired location for recreational boating, fishing, and lakeside summer housing.

Call it a dammed shame, but many say the failure of the Delhi Dam was an accident waiting to happen. Flooding in 2008 had caused a half-million dollars worth of damage to the dam and exceptionally heavy rains (approximately 10 inches in 12 hours) caused the swollen lake to overtop its southern embankment on July 24, 2010.

Rapid erosion of the embankment sped up the outflow and by the next day, Lake Delhi was no more. As the lake and the Delhi Dam were owned by the Lake Delhi Recreation Association, it’s uncertain whether state or federal funds will be used to help rebuild the dam and restore the lake. If not, those who invested in former lakefront property will be out of luck AND lake.

Lake Delton, Wisconsin, USA

If residents of Lake Delhi are searching for some hope, they may find it in Wisconsin’s Lake Delton. Like Lake Delhi, Lake Delton is a man-made lake created in the 1920s as a way to attract visitors to the Wisconsin Dells tourist and vacation area. The lake – more of a reservoir, actually – is only about 10 feet deep and has a surface area of around 260 acres… at least it did, until June 9th of 2008.

Heavy rains had raised the level of Lake Delton and put tremendous pressure on the dikes that separated the lake from the Wisconsin River 800 feet away. The sudden collapse of a 400-ft section of County Highway A that ran on top of the containment dike caused a deluge that completely drained Lake Delton in a matter of hours. Several lakefront homes also collapsed though there was no loss of life. Here’s a short video showing the state of the former Lake Delton 2 weeks after the water drained out:

Iceberg Lake, Alaska, USA

Iceberg Lake, a glacial lake in the Wrangell-St. Elias Mountains area of Alaska, leads a precarious existence by regularly filing and draining, sometimes catastrophically as it did in 1999. The lake is also remarkably responsive to weather conditions as it is pinned between two glaciers whose level of annual advancement and melting decide the fate of the lake.

Scientists exploring the exposed bottom of Iceberg Lake discovered that distinct layers of sediment deposited on after another provided them with a detailed record of the area’s climate that could be traced back to the year 442 AD. Among other findings, the researchers were able to discern the Iceberg Lake did not drain at all during the Medieval Warm Period, a several centuries long warm interlude that existed up until the advent of the Little Ice Age, which lasted from approximately 1600 to 1850 AD.

Lake Haramaya, Ethiopia

Lake Haramaya was a freshwater lake in Ethiopia that was around 30 feet deep and whose shoreline stretched for about 10 miles – not an especially large lake but one that provided residents of the city of Harar with drinking water and farmers & fisherman with livelihoods. The keyword is “was”… overuse by residents, farmers and commercial enterprises caused the lake to drain completely in roughly a decade.

Lake Haramaya is not the only lake in Africa’s volcanic Rift Valley to run dry, and human use (and abuse) is not the only factor involved. Climatologists have noted an increased frequency of droughts over the past several decades and it’s thought that increasing human exploitation of the lake in recent years was enough to tip the balance.

Scott Lake, Florida, USA

Scott Lake is a 291-acre natural lake in Lakeland, Florida, 30 miles east of Tampa. Like Lake Delhi, Scott Lake is owned by the surrounding homeowners who are once again asking state authorities to refill the lake and preserve their property values. Yes, “once again” – Scott Lake has drained before, in the early 1970s, caused by sinkholes opening up in the porous limestone bedrock that lies beneath the lake.

In June of 2006, as many as 4 sinkholes suddenly opened in the lakebed and before you could say “Great Scott!”, Scott Lake was drained. Since then a heated controversy has arisen over demands from wealthy owners of lakeside property that water from Florida’s freshwater aquifer be used to refill the lake. This wasn’t a problem in 1974 but today, water is in short supply as Florida’s population puts increasing strain on the state’s fresh water supplies.

White Lake, Russia

In May of 2005, residents of the village of Bolotnikovo near Nizhni Novgorod, Russia, were shocked to find that most of the water in White Lake had mysteriously vanished. No explanation could be offered for the sudden and silent loss of roughly a million cubic meters of water. “It looks like somebody has pulled the plug out of a gigantic bath,” said a correspondent fr Russia’s NTV. Though an official from a nearby village speculated that the lake’s water flowed into an underground river, others had their own suspicions, believing that “outside forces” were responsible. One man was quoted as stating “I think that America got us here.” It seems that in rural Russia at least, the Cold War never really ended.

Lake Peigneur, Louisiana, USA

Lake located above a salt mine? Scary. Oil drilling in and around said lake? Crazy! But then, we all know that the right hands at big oil companies (we’re looking at you, BP) sometimes don’t know what their left hands are up to… or down to, and in the case of Texaco’s drilling rig in Louisiana’s Lake Peigneur, that would be down to 1,300-odd feet below the bottom of a 10-ft deep lake. When the 14-inch wide drill bit broke through the roof of the mine, the results were predictable yet still spectacular.

Thirty years before the BP disaster in the Gulf of Mexico, carelessness on an oil rig created a chain reaction of events that saw the 1,125 square acre lake (plus several barges, trees and 65 acres of shoreline land) quickly drain into the underlying Jefferson Island salt mine.

This video from The History Channel shows some of the events connected with the catastrophic drainage of Lake Peigneur, filmed by eye-witnesses at the time:

So, what have we learned from the Lake Peigneur disaster? Considering the salt dome beneath the now saline lake is being used as a storage for pressurized natural gas while oil drilling continues in the area, the answer is “not much”.

Aral Sea, Kazakhstan and Uzbekistan

Once the 4th largest inland body of water in the world, the Aral Sea now ranks at just 10th – and falling. A victim of misguided agricultural policies enacted by a nation (the USSR) that is no more, the Aral Sea itself may soon be no more since its main inlet rivers have been dammed to provide water for cotton farms. As the lake shrinks, its waters become more and more saturated with salt , fertilizer and pesticides to the point that an estimated 75 million tons of toxic dust and salts are blown across Central Asia each year. Images of the Aral Sea’s shocking retreat taken from orbiting satellites and spacecraft are, in a word, tragic.

Kazakhstan and Uzbekistan are the successor states to the USSR in which the toxic Aral Sea now lies, and although no longer bound by decrees from the Kremlin, the 2 states cannot agree on how to preserve or even restore the Aral Sea. In the meantime, the loss of over 90 percent of the sea has caused the entire region’s climate to become more extreme, and exposure to poisonous, windblown dust from the exposed lake bed has created a health crisis of immense scope. The shocking image above dates from the summer of 2009.

There is, however, new hope for the Aral Sea as the Kazakh government and the World Bank are working to restore the lake to at least a semblance of its former size. As the images above show (2004 on the left, 2010 on the right), the Aral Sea’s surface area has rebounded 30 percent and depths in some areas have grown from 98 feet to over 130 feet.

Lake Missoula, Northwestern USA

Picture a lake with a surface area of 3,000 square miles containing 500 square miles of water, blocked by an ice dam that is actually an arm of a retreating glacier. This precarious image once existed, in western Montana, about 13,000 years ago and is known today as Lake Missoula. When the ice dam was breached and the lake began to drain westward towards the Pacific Ocean, a flood of biblical proportions ensued.

Not only is it estimated that it took only about 48 hours for the lake to drain completely, this nightmarish scenario is thought to have taken place as many as 40 times over a 2,000 year period. The repeated series of cataclysmic floods scoured vast stretches of eastern Oregon and Washington states into the Channeled Scablands. The remains of an enormous waterfall three times the height and width of Niagara Falls can be seen above top.

Gigantic potholes, gargantuan ripple marks, dry waterfalls and other large-scale geologic features state unequivocally the incalculable power of rushing water – and lots of it. These features show some similarities to features found on the planet Mars and it’s now thought that our neighboring planet was subject to massive flooding events in its younger, wetter days.

Lakes, especially larger lakes, seem to be permanent fixtures of the landscape they occupy. In the geological big picture, however, this isn’t necessarily so and when change comes, it often comes suddenly and strikingly. Water tends to seek its own level under the influence of gravity, that’s just the way nature is… and nature knows no timetable and acts without regard to the works or wishes of Mankind.